Here's a grab from Wiki about the British Sea King and how and why it is different from the US Sea King.

Despite appearances, Westland's Sea King is a very different aircraft from Sikorsky's. Many of the differences between the Westland-built Sea King and the original helicopter were as a result of differing operational doctrine. While the U.S. Navy Sea Kings were intended to be under tactical control of the carrier from which they operated, the Royal Navy intended its helicopters to be much more autonomous, capable of operating alone, or coordinating with other aircraft or surface vessels. This resulted in a different crew arrangement, with operations being controlled by an observer rather than the pilot, as well as fitting a search radar.

But what about Canadian Sea Kings? They were built before the British to operate from Frigates rather than Aircraft Carriers, are they pretty much the same as the USN ones they are derived from? The lacked radar in their early years, so does that make them more reliant on their mother Frigate?

---------------Vegetarian: the ancient tribal word for the villiage idiot; who was too stupid to hunt, fish and ride!

Projects in support of training are also carried out, including the conversion of ASW aircraft to Waterbird configuration to allow for pilot training in ditching procedures, and the conversion of a damaged aircraft into a permanent maintenance trainer.

I suspect that the Canadian military will find reasons to use a few of these old helicopters.

From what I can figure out the RN and RCN came at helicopters from different angles for different reasons, and this is where my interest in these subtle details comes from.

The RN replaced their Gannet AS1/4 which had been in service since 1953 with the Wessex HAS1/3, in effect replacing the primary sensor from the Gannet's radar to the Wessex's dipping sonar. The RN had to use 2 Wessex to prosecute a sub, one for the sonar and another with the weapons, this was not ideal so developed their Sea King to do both and bring back the radar as a sensor. Only after the transition from Gannet to Wessex had occurred did the RN starting thinking they could offload this 'heavy' hunter-killer ASW task from carriers to escort cruisers, initially the Blake and Tiger until the escort cruiser ideas of the 60s became realised with the Invincibles, thus freeing space on the carriers. This was only short lived as the carrier fleet was killed with decisions made in 1968, but I think the basic idea was for the ASW squadrons to go off and do their thing (operating in pairs against an SSN) as part of the wider Task Force/Group under the control of the Admiral/Commodore while the mother ship did other stuff.

The RCN angle was that their 28-29kt frigates of ~1961 weren't fast enough to catch and kill 30kt nuke subs. They needed a method to close that gap and the Sea King of the era could carry both a dipping sonar and AS weapons and bound ahead of the frigate, working closely to corner an SSN as the frigate closes in from behind with the Frigate captain telling the helicopter where to go and what to do.

I think that's the key difference, an Admiral with the Tiger/Blake/Carrier and an RCN FFH in his TF/TG would allocate one SSN contact to a pair of RN Sea Kings and another SSN contact to the RCN Frigate/Sea King pair, but the RCN Sea King wouldn't be hived off to work elsewhere.

---------------Vegetarian: the ancient tribal word for the villiage idiot; who was too stupid to hunt, fish and ride!